Internal-combustion engine



Oct. 27,1925- 1,558,933 F. D. SHEPHERD INTERNAL COMBUSTION ENGINE FiledFeb. 14, 1922 2 Sheets-Sheet l anon M01:

Oct. 27, 1925. 1,558,933 .4 k F. o. SHEPHERD INTERNAL COMBUSTION ENGINEH.106 Feb. 14, 1922 H s s w 5 '32 5: 33 I 60 6 23 I a z -Mo 27/ /42 a;a4 y I [40 3/ I I 6mm,

Patented Oct. 27, 192 5.

UNITED STATES,

1,558,933- PATENT FRANK n. SHEPHERD, or SALT, LAKE CITY, urea.

INTERNAL-COMBUSTION ENGINE.

j Application filed February 14, 1922. Serial No. 53 ,409.

' To all whom it mag concern:

Be it known that I, FRANK D. SHEPHERD, residing at Salt Lake City,couhty of Salt Lake, and State of Utah, a citizenlof the United States,have invented certain new and useful Improvements in Internal-CombustionEngines, of which the following is a specification.

The object of my invention is to utilize to a higher degree than hasheretofore been done, the energy or power of gasolineor like fuel in theoperation of lnternal combustion engines. My invention consists in aninternal combustion engine having the charing yet other forms of myinvention.

Briefly described, my invention comprehends the utilization of a certainportion of hot gases resulting from the explosion of a charge in anengine to'raise the temperature of a successive charge, and an importantcharacteristic of my invention is the avoidance of any rarefaction orattenuation of the gases composing the fresh or incoming charge so thatthe latter when delivered into the cylinder has no less density than ithas when coming from the carburetor. My invention may be embodied in vdiverse or varied forms, and is notdependen t upon application to anyparticular type or style of engine, and hence, though I illustrate inthe drawings various embodiments, and embodiments in engines of variousconstruction, it is to beunderstoodthat the scope of my protection isnot to be restricted only to what is illustrated. It will be found thateach of the structures illustrated comprises a cham- .ber or containerso in communication with vthe combustion chamber of the engine that uponthe compression stroke of the piston upon the suction stroke itwill flowout of such chamber back into the combustion chamber, and mingle or mixwith the gas of Ithe combustion chamber, 13,

an incoming fresh charge, and, being in. a

heated condition, will raise the temperature of the freshcharge and thuspromote greatly its efficiency. Since this mingling or mix-.

ture of the heated gases does not occur until, theincoming freshchargeis in the cylinder,

the gas has the same density it had on leaving the carburetor andundergoes no'change in density such as occurs when a heated charge ofgas is introduced into it between the carburetor and the cylinder, andthe result is that the charge with invention undergoes no loss of B T Uand I get a high degree of compression from the conjoint action of thepiston and the expansion effect of the heated gas thus added ,to thecharge from the chamber or container, aforesaid.

Preferably, I stop the supply of heated gas to the fresh charge when theengine attains toapoint' where heat therefrom is sufficient to get adesired degree of efliciency from. the gas, this stoppage beingdesirable, first because addition of heated gas is unnecessary,

'acertain speed and its parts are heated up and second, to; eliminatethe, danger of;

which acts upon the valve through a plunger or stem, 18, that extendsfrom within the container. where it has a spring engaged head, 19, andreaches to the valve, 14, passingfrom the container, 17, with a slidingfit through a guide hole, 20, in the head,

12, such valve seating means being similar to what appears in my priorpatents, such as 'No. 1,236,991, August 14, 1915; No. 1,240,378,

September 18, 1917 and No. 1,263,133,:

April 16, 1918. v

Alongside the spring container, 17 is a chamber, 21, which is closed atthe top in a gas tight manner by a cover plate, 22, that also closesin'a gas tight manner the top of the spring container, 17, as by a gasket,23, the interior of which chamber, 21, is in communication by a smallbore tube, 24, with adjacent the inletvalve.

It will be seen that on the compression stroke of the piston, a smallportion of the charge of gas confined in the cylinder, (the inlet'valve'being seated), will, as shown by arrows in Fig. 1, be forced intothe chamber, 21, and on the explosion of the charge some of the hot,spent gases will be forced into said chamber, mixing with and heatingthe gas that may be therein, and upon the ensuing suction stroke of thepiston since'the gaseous contents of said chamber are under greatpressure, much in excess of the pressure of the fresh, inflowing gascoming by the open inlet valve, such gaseous contents of the chamber,21, will rush out of the latter into the inflowing stream of fresh gas,and by the inevitable swirling and eddying that is taking place. willthoroughly mix with and heat up the fresh charge. The continuation ofthis action depends on the relative speed of piston and rateof flow ofthefgas from the chamber, 21, and ceases when the speed of the piston isfaster, ant, hence, the length of the passage between chamber andcylinder determines this matter. It is for that reason that I employ thetube, 24, which extends above the chamber bottom to that height which,between successive strokes of the piston, will be too long at thedetermined speed of the piston for the gas to travel to the cylinder andunder such conditions the gas will simply pulsate back and forth in thetube. Thus the interchange of between the chamber, 21, and cylinder isautomatically controlled and involves nothing more than the length ofthe tube. If desired, a needle valve, 25, passed through a packed hole,26, in the cover, 22, may be employed to regulate the size of theentrance at the top of the tube, 24, and thus the rate of flow in thetube nicely regulated. By removing such valve. access can be had to theinterior of the tube through the hole, 26, in the cap for such cleaningas may be necessary. A draiir age hole, 240, in the tube at the bottomof the chamber. 21, is provided for the outlet of any liquidcondensation in the chamber.

Obviously the temperature of gases coming in contact with the tube, 24will be raised because of the necessarily highly heated condition of thetube when the engine is in operation.

As shown best in Fig. 2, a single cap plate or cover, 22. is used fortwo adjacent spring containers, 1?, and the gas-receiving chamber, 21,which is placed between them, a single bolt, 27, only being required tosecure the cover, this arrangement making for economy, but while Iregard it as desirable,

I, of course, do not restrict myself to it.

The cylinder and head shown in Figs. 1 and 2 are water cooled, but ifdesired, as shown in Fig. 1, the water jacket may not extend over aportion of the combustion chamber wall so as to utilize the latter as ahot plate to heat the gas in the cylinder. I prefer, however, tocompletely water jacket the spark plug, shown in Fig. 1.

In the embodiment of my invention shown in Fig.8, I do not have aseparate chamber but utilize the spring container, 170, of the valveseating mechanism as the temporary receptacle for the or gasesinterchanging between the cylinder and such receptacle. In this case thespace around the valve seating plunger or stem, 180, could beused forthe gas flow first in one direction and then in the other, but,preferably, l provide one or more holes, 28, of small bore that extendfrom the cylinder to the bottom. of the container, through which tlowfrom the cylinder into the container is had, return flow therethroughbeing prevented by a check valve, 29, at the end of the hole in thecontainer, the return passage of gas to the cylin der being provided forby making the plunger or stem, 1S0, tubular orhollow, the upper end ofthe passage, 30, thus provided being in communication with the interiorof the container and the lower end in communication with the passagefrom the inlet valve into the cylinder. As the plunger or stem, 180,becomes highly heated, the gases passing through it are additionallyheated by contact therewith, and by taking heat from said plunger orstem, they tend to lower the temperature thereof. The outlet from thepassage, 30, is preferably formed by numerous small radial holes, 31, sothat the hot gas issues therefrom in jets and as they are just above theinlet valve, they enter the incon1 ing body of fresh as soon as itpasses the open inlet valve, 140, and penetrate it in the form of smallstreams flowing in various directions and thus most advantageously actupon such gas. The gas flow is indicated by arrows in Fig. 8.

The check valve, 29, is a ball confined by a cage or guard, 32.

In Fig. 3 the cover of the container, 170, for the valve-seating spring,160, is integral with the side walls, and the bottom of the container isa cylindrical block or plug, 33, screwed into a hole, 34, in the head,120, of a size for inserting the spring, 160, the holes, 28, being insuch plug.

In Fig. 4, I show my invention embodied in an engine not provided withthe mechanism for seating the valve, 141, such as is shown in Figs. 1and 3. In this case, the gas-receiving chan'iber, 210, is secured in agas-tight manner in a hole, 340, in a head, 131, above the valve, 141,and tube, 241, corresponding to the tube, 24, in Fig. 1 establishescommunication between chamber and cylinder, 100, the tube having at itslower end small radial holes, 1 01, from which the hot gases issue insmall jets into the incoming charge. The inlet valve is shown off itsseat in Fig. 4 and the flow of gas from the inlet manifold and the jetsfrom the tube, 241, are shown by arrows. The tube, 2&1, has a drainagehole, 270. Preferably, the outer end of the chamber, 210, is closed gastight by a removable cap, 35.

In Fig. 5, I show my invention embodied in an engine having a similarvalve mechanism to that shown in Fig. 4, but the head,

132, in Fig. 5, is integral, whereas that shown in Fig. 4 is detachable,and the gas-. receiving chamber, 211, in Fig. 5 is inserted in the hole,341, in the head provided for assembling the inlet valve, 142, and whichis usually closed by a solid plug. A plurality shortest; and finally atstill higher speeds it will cease through the shortest tube. A drainagehole, 271, is provided at the bot-- tom of the chamber, and its top isclosed gas tight by a removable cover, 350.

An important characteristic of my invention is the fact that since thespent hot gases follow the portion of fresh gas that enters the transfertube, the first effect on the opening of'the exhaust valves is theremoval of a portion at least of such spent gases through the exhaust,which, of course, have no fuel value, and whose presence in the freshcharge would simply deteriorate it, but before that removal takes placethe heating effect thereof upon the valuable fuel gas in the transferchamber is obtained.

' Tests of my invention show that with a given engine, increase ofpower, and less fuel is required and the engine will pull the load atsubstantially slower speeds than in ordinary constructions and keep inbalance.

In each of Figs. 1 and 3, the valve is shown as simply a disk or headnot attached to the stem on either side; and in each of Figs. 1 and 3, alubricating device is shown in the form of a lubricant-holding bagsuspended in the container so that its lower end is touched by theplunger head when it lifts with the valve and a certain quantity oflubricant is wiped on to the cap, to descend therefrom into the plungerguide hole, the portion of the'plunger adjacent the head is reduced indiameter, and the coil spring, at its upper end is seated in a recessless in diameter than the interior of the container, but none of thesethings nor the form of gas interchange means shown in Fig. 3 arespecifically or particularly claimed herein, but all are so claimed inanother appncation No. 537 ,025 filed February 16, 1922, excepting suchform of gas interchange means which specifically will be claimed in yetanother application.

When in the following claims I use the term. cylinder, I donot therebyuse that term in the narrow sense ofmerely that portion of the engine inwhich the piston reciprocates, but I use it as a matter of convenienceto designate that portion of the engine generally which comprises thespace or chamber between the piston at any part of its stroke and thevalves.

What I claim is:

1. An internal combustion engine having means to successively removefrom and restore to the cylinder on the power-receiving side of thepiston a part of the gaseous contents of the cylinder, said meanscomprising a chamber and a small bore tube extending into the chamber.

2. An internal combustion engine having means to successively removefrom and restore to the cylinder on the power-receiving side of thepiston a part of the "gaseous contents of the cylinder, said meanscomprising a chamber and a small bore tube extending into the chamber,and a valve device to control flow through said tube.

3. An internal combustion engine having means to successively removefrom and restore to the cylinder on the power-receiving side of thepiston a part of the gaseous contents of the cylinder, such meanscomprising a chamber in constant communication with FRANK D. SHEPHERD.

